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1.
Vd'acný P 《European journal of protistology》2007,43(3):225-237
The morphology and infraciliature of two soil haptorid ciliates, Clavoplites haranti sp. n. and Enchelys terrenum (Foissner, 1984) comb. n., collected from Malé Karpaty Mts. and Biele Karpaty Mts. (Slovakia), were investigated using live observation and protargol impregnation. Clavoplites haranti is distinguished from its congeners by a combination of characters including: theronts spatulate to slenderly fusiform, trophonts bursiform, size about 60 x 25 microm in vivo; massive oral bulge with broadly clavate to lemon-shaped, 1.5-2 microm long extrusomes arranged in a ring in oral bulge; ellipsoidal macronucleus and one globular micronucleus; on average 13 ciliary rows, 3 anteriorly differentiated to an inconspicuous dorsal brush. Enchelys terrenum is about 85 x 30 microm in size and differs from its congeners by a combination of characters including spatulate shape; massive oral bulge with 4-6 microm long, fusiform extrusomes arranged in a ring in oral bulge; ellipsoidal to reniform macronucleus and one globular micronucleus; usually 19 ciliary rows, 3 anteriorly differentiated to an ordinary dorsal brush. The diagnoses of the family Enchelyidae and the genus Enchelys are improved. The new genus Armatoenchelys differs from the genera Enchelys and Apoenchelys in having both body and oral bulge extrusomes. Enchelys geleii, E. longitricha, and E. vermiformis are transferred to the new genus. 相似文献
2.
Six non-native invasive fish species from the Slovak part of the Tisa River basin, namely Carassius gibelio, Pseudorasbora parva, Ameiurus melas, A. nebulosus, Lepomis gibbosus, Perccottus glenii, and three gobiid species from the Danube River, namely Neogobius melanostomus, N. fluviatilis and N. kessleri, were investigated for endohelminth parasites. The expanding Asian cestode Nippotaenia mogurndae (syn. Amurotaenia perccotti) (Nippotaeniidea) has been introduced to Europe with its invasive host P. glenii. Pumpkinseed, Lepomis gibbosus, is a new definitive host of Proteocephalus percae and it is reported as the second intermediate host of the bothriocephalidean cestode Triaenophorus nodulosus in Slovakia. 相似文献
3.
We investigated three rare haptorid ciliates, viz., Lagynophrya gibba Kahl (1935), Enchelys lajacola nov. spec., and Spathidium implicatum Kahl (1930), using live observation, silver impregnation, morphometry, and scanning electron microscopy. Lagynophrya gibba, which was rediscovered in peatland soil from Iceland, is referred to a new genus, Kamburophrys, and a new family, Kamburophryidae, based on a unique organelle, the brush membranoid. This structure is near the dorsal brush and composed of very narrowly spaced cilia, about 5 μm long. The genus Kamburophrys has a unique combination of features, viz., an oral cone on the oral bulge, an oblique circumoral kinety, and a subapical hump carrying the three-rowed dorsal brush and the brush membranoid. The Kamburophryidae possibly belong to the order Spathidiida. Enchelys lajacola was discovered in mud from granitic rock-pools (Lajas) in Venezuela, South America. The new species is characterized by a bottle-like shape, a macronucleus with the shape of a curved strand, a heterostichad dorsal brush, and rod-shaped toxicysts. Spathidium implicatum, which was rediscovered in an ephemeral meadow puddle near Salzburg city centre, is neotypified and referred to the genus Apertospathula because it has an open circumoral kinety. 相似文献
4.
You Zhou Guoshu Gong Shirong Zhang Na Liu Jingjing Wang Peili Li Xiumei Yu 《Mycological Progress》2014,13(1):33-43
A new species of the genus Trematosphaeria was isolated and identified from the soil in Jiuzhaigou Nature Reserve, southwestern China. The new taxon was studied based on morphological characters and phylogenetic analyses of three nuclear loci, i.e., the internal transcribed spacer rDNA operon (ITS), and large and small subunit nuclear ribosomal DNA (nuc28S rDNA, nuc18S rDNA). The analyzed Trematosphaeria species were clustered in several clades within the Pleosporales and the genus was shown to be polyphyletic. The new species is introduced as Trematosphaeria terricola, and it is characterized by short-papillate ascomata with suborbicular ostiolum, 3-septate, cinnamon-brown, fusiform ascospores with narrowly rounded ends, verruculose at maturity. Trematosphaeria terricola is compared with morphologically similar species T. confusa, T. mangrovis, and T. pertusa, which differ from the former species in the number of septa, and the shape and size of the ascospores with or without a sheath. This is the first report of a Trematosphaeria isolate from alpine soil in China. 相似文献
5.
The organization and differentiation of primary vascular tissue in isophyllous shoots of Pentadenia crassicaulis and facultatively anisophyllous shoots of P. orientandina (Gesneriaceae) were compared using serial reconstructions and quantitative methods. Despite clear differences in shoot symmetry, both species are vascularized by four sympodia, with trilacunar, split-lateral nodal anatomy. Leaf trace tracheary element number and diameter reflect leaf size differences in P. orientandina: these parameters are significantly greater in the large ventral leaves than in the small dorsal leaves. The median and lateral traces of ventral leaves of this species have a similar number of tracheary elements of equal diameter, while there are significantly more tracheary elements in the median than lateral traces of dorsal leaves. The pattern seen in P. crassicaulis is similar to that seen in the dorsal leaves of P. orientandina. In both species, protoxylem development anticipates differences in mature shoot vasculature. Changes in tracheary element number during ontogeny precede or are approximately coincident with changes in leaf size. These results suggest that the facultative expression of leaf size differences in P. orientandina is associated with opportunistic development and differentiation of the lateral trace. 相似文献
6.
The morphology and morphogenesis of the kinetofragminophoran soil ciliates, Fuscheria terricola n. sp. and Spathidium muscorum Dragesco & Dragesco-Kerneis, 1979, are described. Stained specimens (protargol) are characterized biometrically. The new species differs from the other species of the genus in its body size, body shape, number of kineties, length of extrusomes, and habitat. Both species have telokinetal stomatogenesis, which commences with a proliferation of kinetosomes at those kineties which bear the brosse. Fuscheria terricola does not have a complex perioral ciliature; indeed, it might be that this species has only monokinetids. Thus only a proliferation of kinetosomes and the separation of the kineties takes place in the prospective division furrow. In contrast, S. muscorum differentiates short dikinetid kinetofragments in the region of the division furrow, which are arranged to form the perioral kinety of the opisthe in the intermediate and late stages of the stomatogenesis. The right part of the perioral kinety develops first. This and other studies show that telokinetal stomatogenesis proceeds very differently depending on the differentiation of the oral ciliature; however, detailed studies on the morphogenesis of kinetofragminophoran ciliates are still too few in number for subtypes to be defined. 相似文献
7.
Richard M. Warwick 《Hydrobiologia》1969,34(3-4):392-400
Summary
Eurystomina terricola (De Man, 1907) is redescribed from the British coast. It is characterised by the typical structure of the buccal cavity and in the male a combination of non-winged supplements and a gubernaculum bearing an apophysis. It is proposed that Gerlachystomina Inglis, 1962, be synonymised with Eurystomina. E. terricola prefers coarse relatively dry substrates and is therefore confined to the extreme upper levels of sandy shores and the dryer crevices of rocky shores.
Zusammenfassung Eurystomina terricola (De Man, 1907) von der britischen Küste ist hier noch einmal beschrieben worden. Die Art hat die typische Struktur der Mundhöhle und hat im Männchen eine Kombination von praeanalen Organen ohne Basalplatten und ein Gubernaculum mit Hinterapophysen. Wir schlagen vor, Gerlachystomina Inglis, 1962, mit Eurystomina synonym zu machen. E. terricola zieht einen gröbkornigen ziemlich trockenen Untergrund vor und ist deshalb auf der höchstliegenden sandigen Rornen der Küste, wie auf trockeneren Gesteinspalten beschrenkt.
Résumé Eurystomina terricola (De Man, 1907) est redécrit sur la côte d'Angleterre. C'est caracterisé par la structure typique de la cavité buccale, et chez le mâle une combinaison des papilles ventrales nonailées et un gubernaculum avec une apophyse arriére. On a proposé que Gerlachystomina Inglis, 1962, soit synonyme d'Eurystomina. E. terricola préfére les sables grossiers et relativement secs, et se confine donc aux niveaux les plus élevés des plages de sable et les lézardes plus séches des plages de rochers.相似文献
8.
In total, seven ciliate species were recorded in leaf-litter, moss and soil from a variety of sites in Slovakia for the first
time: Chilophrya terricola Foissner, 1984; Holostichides typicus (Song et Wilbert, 1988) Eigner, 1994; Keronella gracilis Wiackowski, 1985; Notoxoma parabryophryides Foissner, 1993; Parafurgasonia sorex (Penard, 1922) Foissner et Adam, 1981; Paragonostomum multinucleatum Foissner, Agatha et Berger, 2002, and Territricha stramenticola Berger et Foissner, 1988. The paper deals with their distribution, ecology, and comparison with similar species. The shape
and nuclear variants of Paragonostomum multinucleatum are presented and populations of P. multinucleatum and T. stramenticola are morphometrically characterized. 相似文献
9.
C. Tellier C. Vallet-Strouve S. Akoka S. Poignant 《European biophysics journal : EBJ》1987,15(3):177-184
The effect of taurocholate and lecithincholesterol-taurocholate mixed micelles on the structure of isolated intestinal brush border membranes was investigated by nuclear magnetic resonance (NMR). Rabbit brush border membranes isolated by a Mg2+ precipitation step were chosen for this study because of their stability and integrity as revealed by 31P NMR. Incubation of taurocholate with the brush border membranes does not induce significant solubilization of these membranes even when the taurocholate/phospholipid ratio reaches 3.0 1H NMR studies indicate that taurocholate is included in the membrane bilayer at low concentration (3 mM). However this biliary salt produces a size diminution of the vesicles when its concentration increases. Incorporation of lecithin or lecithin-cholesterol in micelles of taurocholate and subsequent incubation with brush border membranes lead simultaneously to a decrease in the 31P NMR isotropic/bilayer line ratio, and to an increase in . These results indicate a protective effect of these compounds against lytic damage of taurocholate. Futhermore the equilibrium distribution of lecithin between mixed micelles and the membrane bilayer is strongly in favour of complete integration of micellar components in the bilayer. These data suggest that uptake of lipids from the micellar phase by isolated brush border membranes involves an interaction of the micelles with membranes followed by a fusion process. 相似文献
10.
LEAF DEVELOPMENT IN ISOPHYLLOUS AND FACULTATIVELY ANISOPHYLLOUS SPECIES OF PENTADENIA (GESNERIACEAE)
Shoots of Pentadenia orientandina exhibit varying degrees of anisophylly, ranging from pairs of equal-sized leaves to pairs of large ventral and small dorsal leaves. In this study we compare phyllotaxis, leaf expansion, and accompanying histological changes in extremely anisophyllous shoots of this species and in isophyllous shoots of the related species, P. crassicaulis. In P. orientandina, decussate phyllotaxis is modified at leaf initiation, and angles of leaf insertion appear to be further changed during leaf expansion. In both species, leaf primordia of a pair are not distinguishable at inception, suggesting an equivalent developmental potential. In P. orientandina, size differences between ventral and dorsal leaves become significant at the P2 or P3 stage, coincident with lamina initiation. Minute dorsal leaves are arrested in their development at the P3 stage and mature without differentiation of multiple epidermis, stomata, mesophyll and most vascular tissue. Variation in dorsal leaf structure in P. orientandina emphasizes the plasticity of leaf development in this facultatively anisophyllous species. 相似文献
11.
《Journal of bryology》2013,35(4):819-823
AbstractConfirmation of the occurrence of the moss Ptychomnion densifolium on the main islands of New Zealand is provided and the features which separate it from the more common P. aciculare are outlined. A brief account of the history of P. densifolium in New Zealand is given and its morphology there is discussed. A key to the two species in New Zealand is provided and habitat differences between them outlined. New Zealand material differs from type locality (Tristan d' Acunha) material in having longer and more twisted acumens, and in this respect is similar to New Zealand material of P. aciculare. New Zealand populations of P. densifolium are recognisable in having stem leaves reflexed from an oblong sheathing base, and well developed basal leaf plications. It is a relatively widespread species in New Zealand, occurring in mostly upper elevation, open sites. 相似文献
12.
The lateral projection area (LPA) hypothesis was investigated by presenting female guppies, Poecilia reticulata with a series of paired males in three experiments. One trait was held constant in each experiment (dorsal fin size in expt
I, body size in expt II, and total LPA in expt III) while body: dorsal fin ratio varied. Females spent more time near dummies
of greater body and dorsal fin size in experiments I and II. The preference functions based on the first two sets of stimuli
showed a similar pattern: the greater the LPA difference between paired dummies, the stronger the preference for the larger
of the two. However, in the third experiment, neither fin size, body size, nor any particular dorsal fin + body size combination
was preferred. These findings support the LPA hypothesis suggesting that increased LPA is more stimulating to sexually receptive
females, and that females consequently prefer larger males. Preference for increased male dorsal fin size/LPA in both P. latipinna and P. mexicana as demonstrated in previous studies, and the more distantly related P. reticulata (shown here) is consistent with common ancestry of the sensory/neural systems in females of all three species and perhaps
the entire Poeciliid family. 相似文献
13.
M. Michelin S. C. Peixoto-Nogueira J. H. A. Betini T. M. da Silva J. A. Jorge H. F. Terenzi M. L. T. M. Polizeli 《Bioprocess and biosystems engineering》2010,33(7):813-821
Aspergillus terricola and Aspergillus ochraceus, isolated from Brazilian soil, were cultivated in Vogel and Adams media supplemented with 20 different carbon sources, at
30 °C, under static conditions, for 120 and 144 h, respectively. High levels of cellulase-free xylanase were produced in birchwood
or oat spelt xylan-media. Wheat bran was the most favorable agricultural residue for xylanase production. Maximum activity
was obtained at 60 °C and pH 6.5 for A. terricola, and 65 °C and pH 5.0 for A. ochraceus. A. terricola xylanase was stable for 1 h at 60 °C and retained 50% activity after 80 min, while A. ochraceus xylanase presented a t
50 of 10 min. The xylanases were stable in an alkali pH range. Biobleaching of 10 U/g dry cellulose pulp resulted in 14.3% delignification
(A. terricola) and 36.4% (A. ochraceus). The brightness was 2.4–3.4% ISO higher than the control. Analysis in SEM showed defibrillation of the microfibrils. Arabinase
traces and β-xylosidase were detected which might act synergistically with xylanase. 相似文献
14.
Cecelia M. Miles Susan E. Lott Cris L. Luengo Hendriks Michael Z. Ludwig Manu Calvin L. Williams Martin Kreitman 《Evolution; international journal of organic evolution》2011,65(1):33-42
Pattern formation in Drosophila embryogenesis has been widely investigated as a developmental and evolutionary model of robustness. To ask whether genetic variation for pattern formation is suppressed in this system, artificial selection for divergent egg size was used to challenge the scaling of even‐skipped (eve) pattern formation in mitotic cycle 14 (stage 5) embryos of Drosophila melanogaster. Three‐dimensional confocal imaging revealed shifts in the allometry of eve pair‐rule stripes along both anterior–posterior (A–P) and dorsoventral (D–V) axes as a correlated response to egg size selection, indicating the availability of genetic variation for this buffered trait. Environmental perturbation was not required for the manifestation of this variation. The number of nuclei at the cellular blastoderm stage also changed in response to selection, with large‐egg selected lines having more than 1000 additional nuclei relative to small‐egg lines. This increase in nuclear number in larger eggs does not scale with egg size, however, as nuclear density is inversely correlated with egg length. Nuclear density varies along the A–P axis but does not correlate with the shift in eve stripe allometry between the selection treatments. Despite its macroevolutionary conservation, both eve stripe patterning and blastoderm cell number vary genetically both within and between closely related species. 相似文献
15.
The effects of spatial habitat structure on population variability of freshwater snails 总被引:1,自引:1,他引:0
Experiments were conducted to examine the effects of a habitat's spatial structure on population variability in two species of freshwater snails (Physa acuta and Austropeplea ollula). To alter the spatial structure of the habitat, vinyl chloride plates were hung in experimental tanks, providing three types of spatial structure: Complex structure, Simple structure and Control (no structure). In Experiment 1, the average number of individuals in a tank did not differ among the three types of structure 2 months after the introduction of the snails, but the variability of the number of individuals in the Complex structure tanks was lowest, whereas the variability in the Control tanks was highest. In Experiment 2, in addition to the spatial structure of the habitat, three types of species interaction were designed as experimental treatments: only P. acuta was introduced into the tanks (P. acuta tanks), only A. ollula was introduced into the tanks (A. ollulatanks) and both P. acuta and A. ollula were introduced into the tanks (two-species tanks). For the P. acuta tanks, the variability of the number of P. acuta individuals in the Complex structure tanks was lowest, and the variability in the Control tanks was highest when the effect of the number of individuals in a tank was subtracted. For the A. ollula tanks and the two-species tanks, there were no significant differences in the variability of the population size among the different treatments of spatial structure. The spatial distribution of P. acuta was more uniform than the distribution of A. ollula on the plates of complex structure. Our results indicate that the spatial structure of the habitat influences the variability of population size (the variance of the number of individuals in different populations during the earlier period after the introduction of the snails), but the effects depend on the spatial behavior of individuals and the interaction with other species. 相似文献
16.
R. David MacLaren & William J. Rowland 《Ethology : formerly Zeitschrift fur Tierpsychologie》2006,112(7):678-690
Sailfin molly (Poecilia latipinna) males possess a large dorsal fin (sailfin) and perform an elaborate courtship display. Females prefer to associate and mate with males of greater body and sailfin size. Evidence supports a single origin for the sailfin species complex from a shortfin ancestor. Unlike sailfin species, males of the shortfin species complex are sexually monomorphic in fin size and exhibit little or no courtship behavior. In this study, we tested the pre‐existing bias and lateral projection area (LPA) hypotheses for sexual selection by examining female mating preferences in the shortfin molly, P. mexicana. Specifically, we presented females with pairs of dummy males differing in: (1) dorsal fin and body size together (holding fin:body size ratio constant); (2) body size (holding dorsal fin size constant); (3) dorsal fin size (holding body size constant); and dorsal fin:body size ratio (holding total LPA constant). Females spent more time near dummies of greater body and dorsal fin size. The preference functions based on the first three sets of stimuli showed a similar pattern: the greater the LPA difference between paired dummies, the stronger the preference for the larger of the two. However, in the fourth experiment, neither fin size, body size, nor any particular dorsal fin + body size combination was preferred. These findings support the LPA hypothesis suggesting that increased LPA is more stimulating to sexually receptive females and that females consequently prefer larger males. Moreover, these data are consistent with results obtained in an identical series of experiments conducted on P. latipinna. The preference for increased male dorsal fin size/LPA by both female P. latipinna and P. mexicana supports the pre‐existing bias hypothesis. Thus, a bias for increased male LPA and consequent selection for enlarged dorsal fins may have preceded the appearance of the sailfin trait within the Molliensia lineage. 相似文献
17.
Effect of salt stress on fatty acid alterations in some strains of Dipodascopsis and Dipodascus spp.
J. Šajbidor M. Lamačka E. Breirerová A. Chrastina P. Pokreisz M. Čertík 《World journal of microbiology & biotechnology》1994,10(2):184-186
The effect of salt stress (8% w/v NaCl) on fatty acid composition of eight strains of Dipodascus and Dipodascopsis spp. varied from being of slight influence only (Dipodascopsis uninucleata), to decreasing the content of 18:2 (D. reesii, D. tetrasperma and D. australiensis) and to decreasing both 18:1 and 18:2 (D. tothii and D. aggregatus) with a concomitant rise of 14:1 and 16:1. With the exception of D. aggregatus, NaCl inhibited lipid accumulation in all strains. Only trace amounts of fatty acids over C18 in chain length were found.J. ajbidor, M. Lamaka, A. Chrastina and P. Pokreisz are with the Department of Biochemical Technology, Slovak Technical University, Radlinskeho 9, 812 37, Bratislava, Slovak Republic; E. Breirerová is with the Institute of Chemistry, Slovak Academy of Science, Dúbravská cesta 9, Slovak Republic. M. Certík is with the Research Institute of Gerontology, Zámocká ul, P.O. Box 25, 901 01 Malacky, Slovak Republic. 相似文献
18.
Stenomitos terricola FBCC-A190 was collected from soils around the trees of Mt. Gwanggyo, located in Yeongtong-gu, Suwon-si, Gyeonggi-do. S. terricola FBCC-A190 is a thin and simple filament with a cell length that is longer than its width. It has a thin and firm sheath, exhibiting a blue-green color. Species belonging to genus Stenomitos is semi-cryptic species with slight morphological differences from each other. They were confirmed as Stenomitos species by analysis using 16S rRNA and 16S–23S ITS. A monophyletic cluster was formed with the previously reported genus Stenomitos, with 16S rRNA gene sequences sharing similarities of 95.9–97.9% except for S. pantisii TAU-MAC 4318. In addition, 16S–23S ITS gene sequencing showed tRNAAla, tRNAIle and V2, similar to the previously reported genus Stenomitos. From these results, Stenomitos terricola sp. nov. was proposed as a new species belonging to genus Stenomitos. 相似文献
19.
M. Ryan Woodcock Michael G. Kippenhan C. Barry Knisley James A. Foster 《Conservation Genetics》2007,8(4):865-877
Cicindela (Cylindera) terricola Say is one of the most widespread and variable species of Nearctic Cicindelidae with six recognized subspecies. Cicindela t. lunalonga Schaupp (1884) is known from few museum specimens collected prior to 1979. The goal of this study was to resolve the uncertain taxonomic
status of C. t. lunalonga using mitochondrial DNA analysis of cytochrome b and cytochrome oxidase subunit I and determine its conservation status.
In phylogenetic reconstruction using distance and parsimony methods, all members of the terrricola group were recovered as monophyletic and embedded within outgroup species of the subgenus Cylindera, while C. lunalonga was recovered as sister to all other members of the C. terricola clade. Cicindela lunalonga exhibited an exceptionally high (mean of 6.36%) pairwise sequence divergence for both genes against all C. terricola surveyed. For the cytochrome oxidase subunit I alone the pairwise divergence was 3.9–4.8% (4.58% avg.). The lowest divergences
were between C. lunalonga and C. terricola subspecies of the American southwest (C. t. cinctipennis and C. t. kaibabensis), rather than with the closest geographic neighbors (C. t. imperfecta). We conclude that based on strict monophyly and pairwise sequence divergence, C. lunalonga is a distinct species. Our study of museum specimens and extensive field surveys suggest this species has been extirpated from all sites in the
San Joaquin Valley and perhaps all but one of the historic sites throughout its range. Thus, it should be considered for Federal
listing as an endangered species. 相似文献
20.
《Biotechnic & histochemistry》2013,88(3):173-174
A study of nuclear structure and chromosome number in the colonial Volvocales has led to the development of an aceto-carmine technic particularly applicable to this group of plants. The genera investigated are Gonium, Volvulina, Eudorina, Pleodorina, and Volvox. Another genus, as yet undescribed in the literature, has also been investigated successfully by this method. 相似文献